Hawai‘i Volcano Overflight: Many Lava Flows
Rainy skies made access difficult for the Paradise Helicopters’ crew on Thursday, Feb. 15, 2018, but they managed to get to the Pali, where lava flows were plentiful.
Several streams of pahoehoe, ending in a‘a were discovered on the Pali itself and more flows just above the cliff scarp combined with the steam for dramatic effect.
A remarkable volume of lava continues to effuse from the area, but doesn’t seem to make any headway toward the ocean.
Kīlauea, the youngest and most active volcano on the Island of Hawai‘i, has erupted almost continuously since Jan. 3, 1983, at Pu‘u ‘Ō‘ō, a volcanic cone, and other vents along the volcano’s East Rift Zone. In 2008, a new vent opened within Halema‘uma‘u Crater at the volcano’s summit, which hosts an active lava lake. About 90% of the volcano is covered with lava flows less than 1,100 years in age.
There are two major types of lava flows, referred to around the world by their Hawaiian names: pahoehoe, a more fluid flow with a smooth to ropy surface; and a‘a, a more viscous flow with a surface covered by thick, jumbled piles of loose, sharp blocks.
Both types have the same chemical composition; the difference seems to be in the eruptive temperature and the speed of movement of the flow.
As much as 99% of Hawai‘i Island is composed of a‘a and pahoehoe flows.